Nick Diaz challenging suspension

Per a response filed to the Nevada State Athletic Commission on March 7, UFC welterweight Nick Diaz is challenging the commission's complaint for disciplinary action that he tested positive for a prohibited substance following a February 4 contest in Las Vegas.

Following a unanimous decision loss to Carlos Condit at UFC 143, the NSAC reported Diaz submitted a urine test that tested positive for "marijuana metabolites". The commission voted later that month to temporarily suspend Diaz's fighters license.

That suspension is unwarranted, according to Diaz's attorney, Ross Goodman, who states that "marijuana metabolites" are not a prohibited substance according to the list used by the NSAC, which is adopted from the World Anti-Doping Agency.

"Marijuana is the only substance that is prohibited; not marijuana metabolites," Goodman told ESPN.com. "The basis to discipline Mr. Diaz is that he tested positive for a prohibited substance. We know he didn't test positive for marijuana. So, you look to see at WADA whether marijuana metabolites are prohibited. They do not prohibit it in any category."

In a sworn affidavit submitted with the response, Diaz stated he has been diagnosed with Attention Deficit Hyperactivity Disorder for which he was prescribed medical marijuana by his physician, Robert E. Sullivan. Medical marijuana is legal in both Nevada and California, where Diaz resides.

Diaz and his camp have said the fighter suspends his use of marijuana eight days prior to a contest. Under the statutes set forth by the NSAC, athletes are not punished for using marijuana out-of-competition.

According to Goodman, the substance Diaz tested positive for was THC-Carboxylic Acid, an inactive marijuana metabolite. NSAC executive director Keith Kizer was unavailable to comment on that claim Monday.

The response filed to the commission, therefore, challenges that Diaz merely tested positive for an inactive metabolite, which is not listed as a prohibited substance.

"You have to test positive for marijuana, as opposed to this inactive ingredient Nick did," Goodman said. "If there's nothing in the rules prohibiting marijuana metabolites, why are we here?"

Athletes are provided the option to submit an application to the NSAC requesting therapeutic exemptions for different substances. Goodman says Diaz did not take that measure because he discontinues use eight days before a contest - long enough for the effects of the active compound in marijuana, THC, to wear off.

The filed document also points to the "long detection window" of marijuana in one's system as a potential reason why WADA does not include metabolites on its banned substance list.

Diaz's legal team argues that since marijuana is not prohibited to athletes out-of-competition per commission standards, it would be unreasonable for its banned substance list to contain marijuana metabolites.

"Why punish Nick, or anybody else for that matter, for a metabolite?" Goodman said. "We're not talking about a cocaine metabolite. We're not talking about something illegal. We're talking about a metabolite that stays in your system for weeks or months."

The UFC had planned to set up an immediate rematch between Diaz and Condit, prior to the NSAC's findings. When hearing the news, UFC president Dana White said he was "beyond disappointed".

Diaz faces a potential one-year suspension for the positive test. In 2007, he tested positive for marijuana following a submission victory over Takanori Gomi in Las Vegas, resulting in a six-month suspension and the result changed to a no-contest.

A formal hearing to sentence Diaz was expected to take place in April; however, Goodman told ESPN.com that date might be delayed due to Monday's filing.